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Is it possible to implement a Python for range loop without an iterator variable?
...ou can just live with the extra i variable.
Here is the option to use the _ variable, which in reality, is just another variable.
for _ in range(n):
do_something()
Note that _ is assigned the last result that returned in an interactive python session:
>>> 1+2
3
>>> _
3
F...
“Inner exception” (with traceback) in Python?
...peError("test")
except TypeError, e:
raise MyException(), None, sys.exc_info()[2]
Always do this when catching one exception and re-raising another.
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What do all of Scala's symbolic operators mean?
... // Syntactic sugar/composition or common method
<= // Common method
_._ // Typo, though it's probably based on Keyword/composition
:: // Common method
:+= // Common method
The exact meaning of most of these methods depend on the class that is defining them. For example, <= on Int ...
Format date and time in a Windows batch script
...== " " set day=0%day:~1,1%
echo day=%day%
set datetimef=%year%%month%%day%_%hour%%min%%secs%
echo datetimef=%datetimef%
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Multiple variables in a 'with' statement?
...Unlike the contextlib.nested, this guarantees that a and b will have their __exit__()'s called even if C() or it's __enter__() method raises an exception.
You can also use earlier variables in later definitions (h/t Ahmad below):
with A() as a, B(a) as b, C(a, b) as c:
doSomething(a, c)
...
How can I filter a date of a DateTimeField in Django?
...
Such lookups are implemented in django.views.generic.date_based as follows:
{'date_time_field__range': (datetime.datetime.combine(date, datetime.time.min),
datetime.datetime.combine(date, datetime.time.max))}
Because it is quite verbose there are pla...
What does the restrict keyword mean in C++?
...h the time.
Edit
I also found that IBM's AIX C/C++ compiler supports the __restrict__ keyword.
g++ also seems to support this as the following program compiles cleanly on g++:
#include <stdio.h>
int foo(int * __restrict__ a, int * __restrict__ b) {
return *a + *b;
}
int main(void) {
...
How can I handle time zones in my webapp?
...s ambiguously used. This looks like a reference: en.wikipedia.org/wiki/Tz_database From what I can tell a "timezone" is "Area/Location", e.g. "America/New_York". That appears to be geographic which is great because for instance America/Los_Angeles means BOTH PST and PDT depending on whether the ...
How do I avoid capturing self in blocks when implementing an API?
... If you're not using Automatic Reference Counting (ARC), you can do this:
__block MyDataProcessor *dp = self;
self.progressBlock = ^(CGFloat percentComplete) {
[dp.delegate myAPI:dp isProcessingWithProgress:percentComplete];
}
The __block keyword marks variables that can be modified inside th...
How do exceptions work (behind the scenes) in c++
...xception
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (throwit)
throw MyException();
}
void another_function();
void log(unsigned count);
void my_catching_function()
{
log(0);
try
{
log(1);
another_f...